Field of the Invention
The invention relates to surgical devices, and more particularly to orthopedic devices for performing knee arthroplasty.
Description of the Related Art
Specific tools and instruments are required for knee arthroplasty, and specifically for the treatment of localized unicondylar cartilage degeneration as a result of osteoarthritis or post-traumatic arthrosis in the medial or lateral compartment of the knee. A critical step in this kind of surgery is the preparation of bones to adapt for tibial resurfacing implants. As the precise location of these implants is essential for a good mechanical function and a long lifetime of the implant, the cuts into the bone material must be performed with high precision.
A device for preparing a proximal tibia for a tibial implant is disclosed in US 2013/0116698 A1. The device provides a main body and a reference bench coupled thereto. Other devices or instruments may be coupled to the reference bench to perform sectional cuts into the bone.
In WO 2013/063418 A2, an instrument for gauging the size, position, and/or rotational orientation of one or more receptions of a proximal tibia for receipt of a tibial implant is disclosed. It comprises a cutting guide with a mounting base, a tibia gauge, and a reference plate to place the cutting guide at a precise location with respect to the tibia.
Another instrument set for preparing a proximal tibia is disclosed in US 2012/0316563 A1. This instrument set comprises a tibial resection block to be fixed to an anterior portion of the proximal tibia. It furthermore has a vertical cut guide having a body, a medial arm, a lateral arm, and a locking arm. The arms provide for a placement of the tibial resection block at a predetermined position of the tibia.
All these instruments or instrument sets have in common that they are comparatively complex. They comprise of several complex shaped parts which are difficult to use, as they allow multiple adjustments to find the correct position for a cut at the tibia. Generally, each setting or adjustment bears the potential risk of a failure. Furthermore, complex tools generally are expensive and bear higher maintenance costs compared to simple instruments and tools.